Electra Flies Dawn One, Solar Powered Climate Observatory

Dean Sigler Batteries, Electric Powerplants, Hybrid Aircraft, Solar Power, Sustainable Aviation Leave a Comment

Dawn One is a solar-powered climate observatory, one of many to come and an outgrowth of a long career for John Langford, Electra Aero’s CEO, and collaborator with Professor James G. Anderson of Harvard University. A seeming callback to John Langford’s human-powered aircraft from his MIT days, Dawn One is a 90-foot span unmanned aircraft system (UAS) destined to fly at stratospheric altitudes (49.000 feet maximum) while observing data for quantitative forecasts of risks in the climate.  We see its first flight from the Manassas Regional Airport in Virginia on September 9.  The assistants in hot pink  and orange vests are Hokies, part of Virginia Tech University, and whose name is explained in a lengthy Wikipedia entry. The “solar-battery hybrid electric research aircraft” is part of the Stratospheric Airborne Climate Observatory System (SACOS) program.  The program will consist of “an ensemble of solar powered aircraft operating for months in the stratosphere,” each “ each “focused on critical climate observing missions …

Rumpled Cathodes Benefit Lithium Sulfur Batteries

Dean Sigler Batteries, Sustainable Aviation Leave a Comment

We like to think of things inside batteries as neatly organized, but Pennsylvania State University researchers may have come up with a less tidy way of making cathodes. Researchers synthesized “highly crumpled” nitrogen-doped graphene (NG) sheets with “ultrahigh pore volume” and large surface area (1,158 square meters– 12,465 square feet or about one-third the area of a football field) per gram.  This large area and high porosity “enable strong polysulfide adsorption and high sulfur content for use as a cathode material in Li-sulfur batteries.”  Interwoven rather than stacked, the wrinkled material provides ample room for “nitrogen-containing active sites.” The batteries, according to the researchers, “achieved” a high capacity of 1,226 milliamp-hours per gram and 75-percent capacity retention after 300 cycles.  This demonstrated capacity and longevity is something other experimenters with lithium sulfur batteries have tried unsuccessfully to achieve. Green Car Reports quotes Jiangxuan Song, one of the researchers on the techniques used. “Lithium–sulfur battery cells using these wrinkled graphene sheets …